Yamaha SS 225 overheat warning light.

[VCinRI]

I have twin 1997 225 SS Yamahas on my 272 Sailfish. The overheat warning light came on a could of times the other day on my starboard engine. Engines have new water pumps and Thermostats. Normal stream of water out of the discharge hole.

Engine and water discharge does not appear to be hot. It first happened at the dock during warmup and was fine all day until the ride in where it went off twice and cleared after a brief shutdown. Then it was fine for the 10 mile cruise in.

Any suggestions as to what it may be? My mechanic is away and was hoping it may be a quick fix I could do myself.

Thanks,
VC

 

[Tucker]

Your poppet valves are bad. About $25 in parts per engine. The design has been changed to ensure the valve doesn't stick in the rubber grommet. Boats.net has an exellent Yam parts list, believe it is shown on crankcase screen. You'll need the new poppet valve, grommet, and housing gasket. Couple things that have bite us DIY have been the propensity to pop the new grommet inside the water jacket. No big deal I've done it and have retrieved it with a guitar string. Also, removing the connectors on the bottom of the ECU makes the job much easier. A battery terminal cleaning brush cleans up the hole real nice. All in all it would be a 4 on the list of difficult jobs I've done.

 

[ahill]

Poppet valves are the problem!
Change both engines.
You may also need to change the housings & bypass tube.